<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>留言板</title>
  <style>
    .container {
      width: 350px;
      height: 300px;
      margin: 0 auto;
      /* border: 1px black solid; */
      text-align: center;
    }

    .grey {
      color: grey;
    }

    .container .row {
      width: 350px;
      height: 40px;

      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .container .row input {
      width: 260px;
      height: 30px;
    }

    #submit {
      width: 350px;
      height: 40px;
      background-color: orange;
      color: white;
      border: none;
      margin: 10px;
      border-radius: 5px;
      font-size: 20px;
    }
  </style>
</head>

<body>
  <div class="container">
    <h1>留言板</h1>
    <p class="grey">输入后点击提交, 会将信息显示下方空白处</p>
    <div class="row">
      <span>谁:</span> <input type="text" name="" id="from">
    </div>
    <div class="row">
      <span>对谁:</span> <input type="text" name="" id="to">
    </div>
    <div class="row">
      <span>说什么:</span> <input type="text" name="" id="say">
    </div>
    <input type="button" value="提交" id="submit" onclick="submit()">
    <!-- <div>A 对 B 说: hello</div> -->
  </div>

  <script src="https://cdn.bootcdn.net/ajax/libs/jquery/3.6.4/jquery.min.js"></script>
  <script>

    $.ajax({
      url: "/message/getList",
      type: "get",
      success: function (messages) {
        if (messages != null) {
          for (var message of messages) {
            var divE = "<div>" + message.from + "对" + message.to + "说:" + message.message + "</div>";
            $(".container").append(divE);
          }
        }
      }
    });

    function submit() {
      //1. 获取留言的内容
      var from = $('#from').val();
      var to = $('#to').val();
      var say = $('#say').val();
      if (from == '' || to == '' || say == '') {
        return;
      }

      $.ajax({
        url: "/message/publish",
        type: "post",
        contentType:"application/json",
        //传的json数据是一个数组，要将它变成json格式
        data: JSON.stringify({
          "from": from,
          "to": to,
          "message": say
        }),
        success: function (result) {
          if (result) {
            var divE = "<div>" + from + "对" + to + "说:" + say + "</div>";
            $(".container").append(divE);

            $('#from').val("");
            $('#to').val("");
            $('#say').val("");
          } else {
            alert("发布失败");
          }
        }
      });

    }
  </script>
</body>

</html>